Automatic code translating system



Jan. 13, 1953 o. CESAREO AUTOMATIC CODE TRANSLATING SYSTEM Filed Dec. 17, 1946 ll Sheets-Sheet l /NVENTOR By -O. CESAREO Arron/Vey Jan. 13, 1953 o. CESAREO AUTOMATIC ODE TRANSLATING SYSTEM 11 shams-Sheet 2 Filed Dec. 17, 1946 l'lllllllll /A/VENTOR 0. CESAREO ATTORNEY l1 Sheets-Sheet 3 Jan. 1.3, 1953 o.l CESAREG AUTOMATIC CODE TRANSLATING SYSTEM Filed nec. 17, 194e www v v wt v, n v v o n F wwm a. +4 "n .LRS

Jan. 13, `1953 o. CESAREO 2,625,328

AUTOMATIC CODE TRANSLATING SYSTEM Filed D60. 17, 1946 11 Sheets-Sheet 4 o CESAREO 2,625,328

AUTOMATIC CODE TRANSLATING SYSTEM 11 sheets-sheet 5 /NVENTOR 0. CESAREO BV AHORA/Ey ....z l u.. y

Jan. 13, 1953 Filed Dec:

Jam E39 1953 o. CESARE@ 625,328

AUTOMATIC CODE TRANSLATING SYSTEM Filed Dep. 17]7 1946 ,l 1l Sheets-Sheet 6 /A/VE/VTOR 0. CESAREO ATTORNEY Jan, 13, 1953 O. CESAREO 2,625,328

AUTOMATIC CODE TRANSLATING SYSTEM Filed Dec. 17, 1946 ll Sheets-Sheet 7 By 0. CESAREO TTOR/VEY Jan. 13, 1953 o. CESAREO 2,625,328

AUTOMATIC CODE TRANSLTING SYSTEM Filed Dec. 1.7, 1946 ll Sheets--Sheetl 9 ATTORNEY /NVENTOR Q CESAREO .l l rYl ATTORNEY Jan. 13, 1953 o CESAREO AUTOMATIC CODE TRANSLATING SYSTEM Fi-1ed Dec. 17, 1946 11 sheets-sheet 11 Patented Jan. 13, 1953 UNITED STATES PATENT OFFICE 2,625,328 AUTOMATIC conn TRANSLATING SYSTEM Orfeo Cesareo, Washington Township, Bergen County, N. J .,K assignor to Bell Telephone Laboratories, Incorporated, New York, N. Y., a corporation of New York Applicationecember 17, 1946, Serial'No. 716,753

. 2 Claims. 1iY

This invention relates to calculators and panticularly to electrical devices by which mathematical calculations may be carried out by the movement of simple electromagnetic means without the use of gear trains, number wheels, cams or other mechanical elements;

An object of the invention is to provide calculating means which will perform long and complicated operations in a minimum of time and with a minimum of apparatus.

Another object is to promote 'economy by adapting as far as possible known and reliable communication apparatus. in accordance with this object a standard'printer of the type used in printing telegraph'systems'is used as a means for recording and displaying the caleulated re'- sults as well as the statementV of the problems and lists of arguments'and other pertinent data.

A principal object of the invention'is to provide means whereby the recorded results will beauto-V matically printed in their correct form.' In many calculators theresults obtained vare attirnes in the form of complements and must'ne'eds therefore be recognized as complements and then translated. In other words thel user of the machine must be constantly on guard lest hemistake a result as a natural number whereas it is a complement. The object of the present arrangement is to automatically translate such results so that the record will always be in proper form and no examination of other' factors' need be considered to discover whether the recorded result is straightforward or inverted.

For the purposes for which the device of the present invention is used the end result of the calculations is a knumber whose character may always be recognizedbyits value. Let us consider the addition and subtraction of lvedigitvnum'bers by way of example. A,six digitregister is employed so that the carryV-outmmaynbe registered as well as thesum `or the remainder. Werhave as a iirst example the addition of two numbersas follows: l Y

but provision must `belmade forsignsj'so we let 0 represent plus and 9` represent minushence this sum becomes 0 l 2 3 Vi 5 9 9 9 9 9 8 Y K 1 (the fugitive one) ,Again suppose we wish to add two numbers of differing sign, as

ril-Ui we should then' have touse a complement, 'since this'actually becomes subtraction, so that the sum would appear as (JOI-l Handi,

, (the fugitive one) o o o 'o' ofi- Once again suppose we wish to subtract a number from one smaller than itself so that our net result is a minus quantity,- as

o o o 0l 1 by using the complement our sum appears as but this is in the form of a complement and it actually represents mo o o o 1 The present invention provides means/whereby if the end result of a calculation'is in it's'complemental form as above; it will nevertheless' be printed in its o1'- dinary form,'as

Now this method is valid so long as the numbers that are handled are small, that is when there is no doubt that is a complement and does not actually represent Since the device of the present invention in a specific embodiment is adapted to calculate errors land an error is always reasonably small we can therefore say that a six digit number beginning with to 4 inclusive is a positive number and one beginning with to 9 inclusive is a negative number. While we may use to represent plus and 9 to represent minus whenever we record a number, we nevertheless consider any calculated number beginning with one of the digits 0 to fi inclusive as positive and any calculated number beginning with one of the digits 5 to 9 inclusive as negative.

In the present device the biquinary system of number representation is used, in which there is one relay operated for all numbers 0 to 4 inclusive and another relay operated for all numbers 5 to 9 inclusive. It, therefore, becomes a simple matter to control the printing of numbers in their proper form. Any number which is the end result of a calculation is printed in the form calculated if its first digit has its 0 to 4 relay operated but is inverted, because it is a complement, if its first digit has its 5 to 9 relay operated.

It should be particularly noted through the above examples that this first digit of a multidigit number enters into the methematical operations in the usual manner and only loses its identity as a digit when it is translated to be printed.

It has also been found, that in one class of calculations it is more expedient to calculate errors with the wrong sign and then to invert the sign at the termination of the calculations. Therefore it is arranged to automatically print the numbers with the sign inverted. Thus a number, the end result of a calculation, such as would in a first class of operations be printed as and in a second class ofY operations be printed as Likewise a number, which appeared as a complement in its calculated form such as would in a rst class of operations be printed as and in a second class of operations be printed as It will thus be seen that the rst digit of. a calculated number will control the form in which the following digits will be printed irrespective of the manner in which such first digit may be translated for printing.

The drawings consist of eleven sheets having twelve figures, as follows:

Fig. 1 and Fig. 2 taken together with Fig. 1 placed above Fig. 2 is a flow chart indicating the manner in which the device in which the present invention is incorporated is operated;

Fig. 3 is a schematic circuit diagram showingl brieiiy the essential elements forming the novel combinations of the present invention;

Fig. 4, on the same sheet with Fig. 3, is a block diagram showing how Figs. 5 to 11 inclusive may be placed to form a comprehensive circuit diagram, in which Fig. 5 shows in part the T, Q and Z registers;

Fig. 6 shows the translator for translating numbers from the biquinary code to the conventional printing telegraph code, together with an inverter for changing such numbers into their nines complements;

Fig. 7 shows certain function relays for transmitting function codes to the printer, the class relays and certain of the starting control relays Fig. 8 shows the distributors for translating the selective characterization of five leads into the conventional time spaced impulses for operating the the printing telegraph apparatus including a conventional printer and reperforator;

Fig. 9 shows certain details of the problem data control circuit;

Fig. 10 shows the steering chain for successively activating the various decimal denominational orders of the various registers from which registered numbers may be transferred, translated and transmitted to the printer and also shows certain steering chain control relays selectively responsive to routine orders issued by the master control circuit;

Fig. 11 shows certain details of the master control circuit, and

Fig. 12 shows the relays directly responsive to the routine orders and which control the steering chain control relays of Fig. 10.

'I'his application is one of a group of seven applications all based on the same arrangement. The Andrews-Vibbard application is a full and complete disclosure and includes a disclosure of the present invention, the other applications including the present application being abbreviated disclosures of certain features of the complete device, as follows:

Serial Applicant number Filing date Y Subject Andrews-Vibbard24. 716, 680 Dec. 17,1946 Automatic calcur. Control circuit.

trical circuit change in which each new circuit operation is dependent upon the successful completion of a previous operation. It consists essentially of a calculating arrangement, a plurality of tape transmitters of the kind commonly usedV in printing telegraph operation for entering both operational orders and mathematical information, a plurality of registers in which mathematical information from the tapes or calculated by the calculator may be stored temporarily and a printing device also of the type commonly used in the printing telegraph art for recording various items of information, including the arguments of the problems, partial results and the final solutions.

In Fig. 1 there is shown a master control tape transmitter |01 which is used to transmit operational orders from a so-called routine tape into the master control circuit |05 which has general control over all the operations of the device. Other similar transmitters are the interpolator tape transmitter |02, theballistic data tape transmitters |03 and |34 and the problem data tape transmitter 05, each with its control circuit. All of these transmit. mathematical information from appropriate tapes and all of this information is generically problem data. That provided by the problem data tape constitutes the arguments of the problem, that from the interpolator tape constitutes corelated or empirical data and that from the ballistic tapes constitutes table information or pre-calculated data such as is usually found in the so-called tables of functions such as trigonometric, logarithmatic, ballistic and other such data. In the Operation of this device the routine tape is operated c'yclically, that is, it runs through its transmitter over one complete set of routine orders necessary for the calculation of a function from one given argument or set of arguments. The problem data tape usually contains a series of arguments and is moved forwardly step by step under control of the master control circuit, the master tape operating through one cycle for each argument. The remaining tapes contain necessary information and may be moved from point to point either forwardly or` backwardly to` transmit information called for by the master control from time to time during the calculating operations.

The calculator here generally shown as included in the broken line rectangle H6, consists primarily of four relay registers, the A register l |28 constituting an augend element, the B` register |29 constituting an addend element and the C register ili and D register being used alter natively as sum elements. All problems presented to the calculator are in the form of problems in multiplication and the calculation is actually performed by summing the values registered at various times in the A and B registers. For this purpose a set of multiplying relays |21 and a set of multiplier relays |33 are provided by means off which a rnultiplicand operating the multiplying relays |2 may be multiplied by one digit at a time of the multiplier which operates the multiplier relays |33. There is provided a set of switchingrelays |3| for determining into which register, the C register |25 or the D register |33 the values in the A and B registers shall be summed; Values stored in theV D register |33 may be transferred only to the B register |29, by way of an inverter |32; This is a means by which the value being transferred from the D register to the B register may be transferred as it isor in its complemental form. Values stored in the C register |25 may be transferred either to the A register or transmitted out over the C multiple l i7 for transfer to any one of the various registers shown in Fig. 2; t

The calculator H6 is under general Kcontrol of a steering cicuit i2! whichk controlsthe various steps in a multiplying calculation cycle. When .a problem inl division is `presented an additional circuit, the division steering'circuit |22'isv brought into action to malore the, necessary changes and alterations in the calculating cycle. The cut in relays |28 ordered into operationv by the master control circuit m6 through the co'de distributing relays lilopcrate to activate one decimal denominational order at a timeuofcertain registers which then transmit over'the` R1 multiple |51 to operatethemultiplier-relays under control of the steering-circuit |2|. The division steering circuit, ordered into operation over the path |24. besides modifying the calculation cycle provides a supply of multiplier digits over the R multiple H5 to themultiplier relays |33 as trial quotient digits and transmits the correctly calculated quotient digits over the C multiple I1.

The novel combinations of the present invention concern generally the arrangements for recording the end resultsof the calculations. In a specific embodiment of the inventionsuch calculated numbers are temporarily deposited in the T register from which the printer control circuit lill orders them translated and transmitted by the transmitter distributor ||2A to either the printer H3 or the` reperforator H4. It may be noted that the reperforator may be used to prepare `table tapes, that is the calculating device may be used to calculate values of ballistic constants or other values which WillV be used in solving other problems so that by transmitting the calculated information to the reperforator H4 instead of to the printer ||'3,. a tape may be prepared suitable for use in one of the table tape transmitters such as one of the ballistic tape transmitters. Of course such a tape at any time thereafter may be run through a tape transmitter and a printer to produce a printed record of the calculated information. The means of the present invention is especially useful in this connection since4 it is desirable to enter all numbers into the calculator in their normal or natural form and not in the form of complements.

Fig. 3 is. a schematicv circuit diagram to show briefly the essential elements forming the novel combinations of the present invention. All of these elements are set forth in more detail hereinafter and in stillY more. detail in the said Andrews-Vibbard application.

Relays 30| to 304v represent the U or first-decimal denominational order of a relay register (the T register),r relays 305 t'o 308r represent the V or second. order thereof and relays 309 to- 3|2- represent the Z or sixth order: thereof. There are seven relays in each order divided into a binary group of two relays designated 00 and 5 and a quinary group of five relaysv designated (l, I, 2, 3 and 4. Any one of the'ten digits may be represented by the operation of onegrelay` from each group. Thus, the digit 2 is representedlby the operation of the 00 relay ofthe binary group and the 2 relay of the quinary group and like wise the digit 8 is'represented by the operation of the 5- relay of the binary group and the 3 relay of the quinary group. The value of the digit is equal to the sum of the two numbers used to designate the two relays which are operated. The other relays of each order4 and the relays of the other orders are not shown. The Q and Z registers 3|5 and 3|B are indicated by blocks.

Numbers may be read from the problem data tape 3|3 into the. C multiple 3|4 or from the calculator 3|'I intoA theC multiple to setthe T', Q or Z registers. Generally speaking numbers which are read from the tape' into the T reg-- form of complements will lie-inverted andprinted in their true forms'.

Generally throughout the calculating device Where a plurality of operations are to be sequentially performed the control of this sequence resides in a progress circuit or steering chain. In the present case the six digits deposited in the T register must be sequentially transmitted to the transmitter distributor leading to the printer and hence a steering chain is provided the rst relay only of which is here shown as CH-l relay 3l8. This relay when operated will activate the circuits through the U order relays of the T register.

In the operation of the calculating device the whole sequence or operations is controlled by the master or routine tape 3|9 through the master control circuit 320. The initial order issued by the routine tape is to operate a class relay, of which two are here shown, the CL-l relay 32! and the CL-2 relay 322. When one of these relays has properly responded to the order for its operation it returns a satisfaction signal to which the master control circuit responds by advancing the routine tape 319 and issuing the next routine order.

Now one of the routine orders which may be issued is to print the number stored in the T register starting with the U order. This order is issued through a ground placed on the PTU lead 323 by the master control circuit. This will result in the operation of the PT- relay 324 which in turn will operate the T6 relay 325.' The plus PL relay 326 responds to the operation of the T6 relay 325 and connects the seven biquinary leads multipled to the corresponding relays of each of the six orders of the T register to the corresponding seven biquinary leads included in the bundle 32T leading to the translator. The translator consists of a set of seven biquinary relays including the P relay 328, the P relay 329, the Pi) relay 330 and the Pil relay 33l which may be operated in accordance with the biquinary code and which in turn will place grounds on the ve conductors leadingto the .segments of a conventional printing telegraph transmitter distributor 332 to transmit .the conventional printing telegraph codes to vthe printer 333. The particular codes used are the' tenl codes each having three marking signals and two spacing signals as indicated by the three armatures of each of the quinary relays 333 and 33l.

In due time the chain start ground will be established and will result in the operation of the iirst steering chain relay 313. Thereupon the leads 333 and 335 will be grounded and since relay 325 is operated this will result in the grounding of the U order activate leads 333 and 337. Now in accordance with the setting of the relays of the U order of the T register the corresponding relays of the translator will be operated and the digit represented thereby will be Y transmitted and printed. Through means not shown here the completion of the transmission of this digit will cause an advance whereby the next steering chain relay will operate. This will ground another pair of leads now connected through the armatures of the T3 relay 325 to affect the activate leads 338 and 333 of the V order of the T register whereby the digit stored therein will be transmitted and printed. The remainder of the six digits in the T register Will be likewise transmitted and printed.

Another routine order may result in the transmission over the trunk 340 of the numbers stored in the Q and Z registers by translation, transmission and printing.

Still another routine order which may be issued will result in the grounding of the PTVi lead 3M which will result in the operation of the PTE relay 332 and the T5 relay 343. This order directs that the number in the U order of the T register be translated to a -lor sign and that the remaining digits in the T register starting with the V order be printed. Means are provided so that the ve digits printed will be printed without change if this ve digit number is in its natural form but will be inverted and printed in its natural form if it is stored in its complemental form. Further means are provided so that if the class 2 relay is operated the sign will be printed as registered but if the class 1 relay 32! operated the sign will be inverted before being printed.

In this instance the PT-S relay 322 will ground the lead 333 so that if the TUM) relay 3D! is operated, indicating one of the digits 0 to 4, then the plus relay PL will be operated but if the TUE relay 392 is operated, indicating one of the digits 5 to 9, then the negative relay 335 will be operated. The negative relay inverts the digit in its transmission from the T register to the translator. Also the T5 relay 333 will ground the activate lead 346 whereby the digit in the U order of the T register will be transmitted through the sign inverter controlled by the class relays 32| and 322. The T5 relay 333 also causes the operation of the (i) relay 337 to cause the binary registration of the first digit to be translated into the proper code for transmission to the printer 333.

These operations may be illustrated by pointing out that if the number Under code Under code PTU P'IVzl:

Class l 9 87654+l2345 C1ass2 987654--12345 The schematic circuit diagram shown in Figs. 5 to 12 inclusive arranged as indicated in Fig. 4 is an elaboration of the schematic of Fig. 3 showing many of the circuits described in connection with Fig. 3 in great detail. Nevertheless, even here the showing is not complete though the circuits are believed to be clearly indicated. For instance in Fig. 5 the T, Q and Z registers are only indicated. The T register is one having six decimal denominational orders each consisting of a biquinary group or" seven relays. The relays TUM), TUS, TUO and TUd represent the seven relays of the U order of the T register which are generally designated d, 5, El, I, 2, 3 and d, respectively and which operated in pairs, one from the lbinary group B9, and 5 and one from the qunary group t, l, 2, 3 Vand i represent a digit whose value is the sum of the numbers used as the designations of these relays. In the same manner the V and Z orders of the T register, the V and Z orders of the Q register and the V and Z orders of the Z register are indicated. The inverter by which a digit represented in the biquinary code may be inverted into its nines complement is indicated by the positive and negative relays. The inverting means for the binary portion is complete but the equivalent means for the quinary portion is only indicated. Thus in inversion becomes 5 becomes OO 0 becomes 4 l becomes 3 2 becomes 2 3 becomes 1 4 becomes 0 whereby, by way of example the digit 8, represented by the operation of the 5 and 3 relays Icecomes the digit l, represented by the operation of the 00 and relays (beyond the inverter).

In the operation of the device in which the present invention is incorporated and which is disclosed in complete detail in the said Andrews- Vibbard application, a master or routine tape is provided to have general control of the sequence of operations therein. The master control circuit issues orders, each one of which upon completion terminates in the transmission to the master control circuit of a satisfaction signal which results in the advance of the routine tape and the transmission of the next order in sequence. The master or routine tape is in the form of an endless loop and normally or in the event of trouble moves to an end of cycle position from which it advances in a new cycle. The rst code position on this tape is a blank and is known as the priming operation. When the tape has been moved to this position it cannot move therefrom until the calculating device as a whole, which means each component thereof is primed or in a proper ready condition.

This may be noted byconsidering the circuits of Fig. 11. The blank code is always arranged to be read as a units code of a two digit combination. Hence after a tens cod-e has been read the tens switching TS relay I |00 operates, the transfer TF relay Hill operates and when conditions are ready for reading the units code into the units relays, the TS-| relay I |02 operates. Thereupon a circuit is established from ground armature 3 and front contact of TS-I relay I |02, front contact and armature I of EC-I relay H03, the NC conductor H04 which may finally be traced to the STP relay H05 to advance the tape H06 to the next code.k The NC circuit is known as the new course circuit and will be completely closed only when the various component circuits of the complete device are ready to proceed. Assuming then that the various circuits have been driven to their proper starting conditions this extensive circuit may be traced from conductor H04, over the back contact and armature 5 of the auxiliary recycle relay of the Problem data control circuit RC-I relay 900 armature 4 and back contact of NC-2 relay 90|, armature 3 and back contact of NC relay 902, armature I and back Contact or RC-l relay 900, conductor 903, the down check circuit of the class relays in Fig. 7, including in series a back contact and armature of each of the class relays 100, |0| and '102, conductor 103, the back contact and armature e of the EP relay |000 (end of progress relay) conductor Iiii, back contact and armature It of EP-I relay |200, thence through similar check circuits in the ballistic data control circuit and the interpolator control circuit |202 to the NC-l conductor |263 which finally connects to the S'IT conductor |204 leading to the STP relayY H05. The closure of this circuit guarantees thatl the calculating device as a whole is ready to proceed to the calculation of a function.

The operation of the STP relay through its operation of the stop magnet H01 moves the tape to its next code, the tens digit of a two digit number. By the movement of its armature 4 the relay I |05 releases the EC relay H08 and this in turn releases the EC-I relay H03. Thereupon the TSL relay H09, the TS relay H00, the TF relay ||-0| and the TS-I relay H02 are released, the TF relay 0| in turn releasing the STP relay H05 thus leaving .the master control circuit in normal condition, with only the start relays, ST relay |||0 and ST-I relay operated.

A circuit may now be traced from ground, armature 5 and frontoontact of ST-I relay I, armature I and back contact of STP relay H05, back contact and armature 2 of the M relay I2 to the marking contacts of the tape transmitter whereby the code now positioned therein is read over the back contacts of the transfer relay l I0| into the tens relays, athereby selected number of which operate and lock to conductor I3. When the tens relays have been properly operated a ground will be placed on conductor HM, the back contact and armature 2 of TS-I relay H92, the armature and back contact of GD relay H5 to the winding of TS relay |00. Relay |05 operates and among other duties closes a circuit from armature 4 of ST-I relay to operate the M relay |||2 which causes the stop magnet to operate to advance the tape to the units digit of the codenow being read. The M relay closes a circuit for the TF relay ||0| which transfers the transmitter nngers to the units relays. Relay ||0| through its armature 8 closes a circuit from the GD relay I5 to the down check circuit of the units relays so that if and when these relays are all properly released the GD relay |||5 will operate to release the tens relays and at the same time cause the operation of the TS| relay 02 through opening the original energizing circuit for TS relay H00. When TS-I relay operates the M relay H I2 is released and ground is again placed on the marking contacts of the transmitter to read the code from the tape into the units relays. These properly operated will ground one of the code leads through the operated code relay which has responded to the tens relays such as code lead |||5 closed by relay Now it need only be mentioned further in relation to the master control circuit that the grounding of a lead such as the lead |I|6 constitutes the issue of an order. The master control circuit will therefore remain in the condition now attained until this order has been carried out whereupon a satisfaction signal (a ground placed on the STP lead |204) will cause the master control transmitter to advance.

In a typical example of the use of the calculating device fully described in the said Andrews-Vibbard application, the rst order to be issued is one designating the class of operations that will be performed. A code lead such as I6 will be grounded leading to a class relay, such for example as the lead |206, leading to CL-I relay m2. This relay would then operate and lock to conductor 104, which Will be found grounded at a front contact of the ST-4 relay HI8. The proper operation of the class relay will extend the ground for its operation to conductor |204 as a satisfaction signal whereupon the master control tape will be advanced.

A succeeding order will be the grounding of the PDTQZ lead which orders the argument values recorded in the problem data tape to be read off and registered in the TI Q and Z regis- 11 ters. The code lead PDTQZ is shown (in Fig. 12) as the conductor I 201 and may be traced through the armature 3 and back contact of the EP-2 relay |002, conductor |003, the back contact and armature 8 of the RC-I relay 900. Now it may be noted that at the start of operations the problem data tape has been moved until it has encountered a ve hole code which precedes each block' of information recorded in such tape. Therefore the ER relay 904 and its companion ER-I relay 905 will be operated at this time so that the ground on the PDTQZ lead at armature 8 of relay 900 will be extended over the front contact and armature 3 of ER-I relay 905 to the winding of the T relay 906. Now through further means not shown here the PDTQZ lead causes the T register cut-in relay indicated by the horizontal line 500 to be operated (and after the T register has been illled, then the Q register cut-in relay and nally the Z register cut-in relay) so that a ground is extended over conductor 50| the front contact and armature 4 of the T relay 905 to the chain start lead where it may be traced through the armature I and front contact of relay 906 to the winding of U relay 901. This relay operates and causes the operation of the U-I relay 908 whereupon the translator relays set from the problem data tape 909 will transmit to the U order of the T register. This is suicient to indicate how in response to an order issued by the master control circuit, the arguments of a problem may be read olf of the problem data tape and recorded in the T, Q and Z registers. Thereafter other orders issued will steer the operations of the device to perform certain calculations. It need now only be noted that eventually the calculator 502 will derive a number which may also (the T register in the meantime having been emptied) be registered in the T register.

In connection with the present invention it may be noted that any numbers read from the problem data tape into the T register will certainly be in their normal form and hence no special provisions have to be made in connection with such numbers. Therefore when such numbers are to be printed the master control circuit will issue an order (PTU) which will result in the digits being read from the T register to the printer without change, starting from the U order thereof.

However, a number which was registered in the T register from the calculator 502 may be either in its normal form or in its complemental form and hence a code (PTVi) is provided to automatically warrant that the number will be printed in its normal form.

Let us now assume, by way of example, that the digits 9, 8, 7, 6, and 4 are registered in the U, V, W, X, Y and Z orders of the T register respectively and that these digits have been transmitted there from the calculator 502. This number, the end result of a calculation, is to be printed. The routine tape will therefore transmit an order which will result in the grounding of the PTVi code lead shown in Fig. 12 as conductor |208. Ground on this lead Will be extended over armature 3 and back contact of EP-I relay |200, the normal contacts of armature 5 of PT-5 relay |209, and thence to the winding of relay |209 and battery. Relay I 209 responds and locks to conductor |2|0 which is grounded at armature 2 of ST-4 relay II I8 (Fig. 11) under control of the end of progress EP relay |000. 'I'he original ground on conductor I 208 is. 110W @Xnld by armature 5 of relay |209 to conductor |2I I where it will remain until this operation is completed and the EP-I relay |200 is operated.

Upon the operation of relay |209 ground will be extended over armature 4 and front Contact of relay |209 to the start conductor I2I2, to be extended through the normal contacts of armature I of CD relay I2 I3 to the winding of ST relay I2 I4. This relay responds and temporarily opens the connections to the steering chain selecting relays (T-B, T-5, T-3, Q, Z and CR.) until a check has been made to see that the circuit is in proper condition.

Thus the winding of the CD relay I2I3 is con nected by armature I of ST relay I2 I0 to a series circuit involving an armature and back contact of each of the steering chain selecting relays and each one of the steering chain relays to a ground on armature of CH-I relay |0055. If all of these relays are, as they should be, released then CD relay I2I3 will respond, will lock tc the ground on the start conductor I2 I2 and will release the ST relay I 2| 4. The T-5 relay |005 will now be operated from armature 3 of PT-5 relay |205. Through armature 2 of PT-5 relay |209 ground is extended to TPSN conductor I2I5 which may be traced to armature 2 of the binary TU-OO- relay 502 and TU-5 relay 503. Since l have assumed that the digit 9 is registered here, the TU-5 relay will be operated and this ground will be extended over conductor 594 to operate ie NG relay 600 which will invert each of the digits transmitted from the T register to the translator of Fig. 6.

Upon the operation of CD relay I 2I3 and the subsequent release of ST relay I2Il, ground on, armature 9 of ST relay I2 I4 is extended over the front contact and armature 9 of CD relay I2I9 to the windings of EP-2 relay I 002 and EP- relay |200. The ground on conductor |2|| now extended over the front contact and armature 9 of EP-I relay |200 to conductor I2|6 leading to STP-M relay |007 which responds and grounds the STP conductor |204. This constitutes a satisfaction signal to the master ccntrol circuit which will therefore advance and order some other circuit operation to be performed while this printing operation is being carried out. As soon as the master control tape advances ground is removed from conductor |202 and the STP-M relay |091 is released.

In the master control circuit the ST-e relay I II8 places a ground on conductor I|I0 which may be traced through armature 8 and back contact of ST relay I2I4, front contact and armature 8 of CD relay I 2I3 the chain start lead I 2|? for the steering chain of Fig. 10 which leads to CH- relay |000. This relay responds and transfers the down check ground on its armature I to a chain circuit leading to conductor I 005 leading through the normal contacts of armature 2 of CD-I relay '|05 to the winding of ST-I relay H39. Again a check is made by connecting the winding of CD-I relay to a chain circuit involving an armature and baci; contact of each of the relays, STP-701, W-l08, ZI-lS, LTRS-lii, i-'Ii i, LF-'II2, CRA-H3, SPA-'H4 and the biquinary translator relays Pfl-|, Pit-902, P24503, PI-Glll, PO-605, P5-E09 and POO-S01 to ground. If all of these relays are, as they should be, released, then CD-I relay 705 will respond, lock to the ground on conductor |009 and release ST relay 106.

The conductors 'H5 and I I6 are now grounded. Conductor III is extended through armature l and front contact of CH-I relay Ia, armature IE! and front contact of T- relay |905, conductor i903 the Winding of irelay 'IIS to battery and relay III responds. Ground cn conductor 'IIS is extended over armature 5 and front Contact: of Cil-I relay I elle, armature II and front contact of 'T25 relay H305, TPC conductor Ilieii to the armatures 3 of binary relays 5de and 533 and since relay 5&3 is operated to conductor 5%5, armature 2 and front contact of CL-I relay 102, conductor l' Il', thence over armatures e and 6 of i relay lli to ground the a and c conductors leading the a and c segments of the transmitter distributor i300.

In Fig. 8 there is shown schematically a printer SSI which by a jack and plug arrangement may be connected to a line S92 and a reperforator S93 which by a similar arrangement may be connected to a line 80d. By means of a key 3&5 the line 80% coming from' the distributor may be switched from its normal connection to the line 8&2 to the line 8M. rihe key 3&1 will similarly switch the line 893 coming from the distributor des from its normal connection to line 04 to the line 802. The two keys @S5 and Sill may be mechanically connected to act together. Thus either the printer 8m or the reperfcratcr 803 may be connected to receive from either distributor. The distributor 8S9 may be used to print from a prepared tape and is thus useful for checking purposes and for preparing duplicate tapes.

With the terminals of the printer Sel plugged into the jack SSE a circuit is established from battery, the printer the ring 8 I 0 of the distributor, the stop segment thereof on which the brush rests when not in motion the winding of CP relay 'I I8 to ground. Relay 'i I8 is therefore operated when the circuit is ready to carry out a printing operation. Therefore upon theoperation of i relay lli a ground is extended to the ST-2 conductor lid. With relay 'EIS operated this ground will be extended over armature 2 and iront Contact of relay ll, armature 2 and baci; contact oi ZI relay lil@ the winding of W relay TSS to battery and relay '5&8 will respond and lock to conductor llt. This will close a circuit from the ground on conductor 1 I S over armature I and iront contact of CP relay TIB, armature I and back contact of Zi relay lili?, armature I and 'iront contact of W relay lilS to the clutch magnet til of the deslrtbutor 895 whereby the distributor is unlatched to make one revolution during which the brush will ride over the start segment, the ve code segments and come to rest again on the stop segment. As the brush leaves the stop segment CP relay "i3 releases and closes the ground on conductor l' IS over its armature 3 and back contact, iront contact and armature 2 of W relay iut, the winding of ZI relay R3 to battery. Relay ist operates and locks to ground on conductor "i I El. When the distributor arm has made its revolution and come into contact with the stop segment again, relay iid will operate and this will now close a circuit from ground on conductor lle, armature 2 and front contact of relay ile, armature 2 and front Contact of Zi relay the winding of STP relay 707 to battery. Relay operates and locks to ground supplied by armature I of CD-l relay N5. Through its armature 2 the STP relay 10'! closes the chain start ground used for operating CHJ relay itil@ to armature 3 thereof and thence to winding of Cil-2 relay IOI0. Relay IDI!) operates and holds CH-I relay |004 operated until STP relay 10'! releases. With two of the steering chain relays operated, the ground supplied by armature I of CH-I relay Ill is removed from conductor H306, whereby CD-I relay is released. This takes the ground off of conductors 'H5 and H5 whereby the i relay 'HI is released and the ground on conductor III is removed. In turn the ground on conductor 'H9 is removed so that in turn relays lill, 'HBO and T09 release. The release of relay 'l'l opens the circuit for CH-I relay H204 and this relay returns to normal thus rendering the CEI-2 relay IGIO fully effective.

When CH-I relay i004 becomes released and CH-2 relay II is operated ground is again placed on conductor H305 to operate ST-I relay When the down check circuit starting with the ground on armature I of POO relay 60"! shows the relays of the translator circuit to be in properly released condition the operations for the printing of the digit in the V order of the T register will be started.

Now it was noted that during the operation of the i relay lI I that the a and c conductors leading to the transmitter distributor were grounded. In accordance with the following table of codes it will be seen that a sign was printed. It may be noted that the digit 9 in the U order of the T register would normally result in the printing of a sign, but this is reversed since in class 1 operations it is easier to calculate the errors with the wrong sign and to then invert the sign through the contacts of the class relays. In the following table the O represents marl; (correspending to a perforation in a tape) and a blank represents a space.

After Cl--E relay IOIG has been operated, CH-I relay has been released and conductors 'I I 5 and 'H6 have again become grounded these ground connections will be extended over armatures 6 and 'I of CH-2 relay IlI0 and armatures 8 and 9 of T-5 relay |005 to the TPVOO and TPVO activate leads ISII and I SI2 leading to the binary group and the quinary group respectively of the V order of the T register. It will be ren embered that the digit 8 was assumed to be registered here and hence the TV-5 relay 506 is operated and the ground on TPVOO lead IOII is extended to the 5 lead E01 but is inverted by the NG relay 60S to ground the OO lead 608 and thus cause the operation of the POO translator relay G0?. In the same manner the 3 quinary relay in the T register is operated but since the NG relay is operated the P-I relay 604 will be operated. Now with relays 601 and 604 operated it will easily be seen that the a, b and d code wires leading to the corresponding seg- 

